This scripture refers to the ceremony of consecration of the firstborn. The Israelites understood the firstborn of any living thing as specially belonging to Jehovah. All the firstborn of the beasts were sacrificed, in remembrance of the Passover and in looking forward to the atoning sacrifice of Jehovah himself. In verse fifteen God makes an interesting distinction between the firstborn of the Egyptians (who were slain along with the firstborn beasts) and the children of Israel, who were spared. Nonetheless, God commanded them to redeem the firstborn male, which was necessary before he could inherit his father's name and house.Exodus 13:12-15
12 That thou shalt set apart unto the Lord all that openeth the matrix, and every firstling that cometh of a beast which thou hast; the males shall be the Lord’s.
13 And every firstling of an @#$ thou shalt redeem with a lamb; and if thou wilt not redeem it, then thou shalt break his neck: and all the firstborn of man among thy children shalt thou redeem.
14 ¶ And it shall be when thy son asketh thee in time to come, saying, What is this? that thou shalt say unto him, By strength of hand the Lord brought us out from Egypt, from the house of bondage:
15 And it came to pass, when Pharaoh would hardly let us go, that the Lord slew all the firstborn in the land of Egypt, both the firstborn of man, and the firstborn of beast: therefore I sacrifice to the Lord all that openeth the matrix, being males; but all the firstborn of my children I redeem.
Scripturally the word firstborn denotes the birthright son within a given family unit. In the scriptures I feel I've noticed a rather striking pattern, all centering on this office of being the firstborn.
Having the birthright, a firstborn receives exclusive blessings and priveleges, even those associated with the father he inherits them from. He is also given however a responsibility, to share and extend those blessings to the younger siblings, that they might be partakers of the same. The firstborn and his associated mission is the means by which all the children might share in the blessings of their father, and of himself. The father can only make one child his heir, but the heir may share that inheritance with his fellows.
Israel - Firstborn among the Nations
The Lord views the families/nations of this earth as one larger family unit, his children. Among these children however, he has called Israel his firstborn. Consistent with the pattern, Israel received exclusive blessings. They were blessed with prophecy, miracles and visions. Most of all however, they were blessed with a knowledge of the Lord. This is symbolically represented in his attempting to show himself to them on Mount Sinai. Among the nations of the earth, Israel were and have ever been specially blessed with his presence and privy to his truth. This is why Jesus came to the Jews, because they were his peculiar people.Exodus 4:22
22 And thou shalt say unto Pharaoh, Thus saith the Lord, Israel is my son, even my firstborn
So Israel was specially blessed, what about their responsibilities as the firstborn? To share what they have received on account of their inheritance. From the beginning the Lord's purpose in naming Israel as his firstborn was that all nations of the earth might be blessed. Israel was intended to be the vehicle by which all nations might likewise share in those special, exclusive blessings.
Ephraim - Firstborn in Israel
If it weren't for Joseph of Egypt, the house of Israel wouldn't have lasted even a few generations. His is the archetype of that firstborn son who is specially raised up, "redeemed", and then proceeds to be the means of saving his father's house.Jeremiah 31
9 They shall come with weeping, and with supplications will I lead them: I will cause them to walk by the rivers of waters in a straight way, wherein they shall not stumble: for I am a father to Israel, and Ephraim is my firstborn.
So if Ephraim is the firstborn in Israel, what are his priveleges? The restoration of the Gospel of Christ, through the hands of Joseph Smith Jr. What are his responsibilities? To share it! which we can witness easily today as missionaries cover the earth spreading the good news of the Restoration. The son receives this special redemption at the hands of his father, then proceeds to make it available to all the younger siblings and their houses.
Jehovah - Firstborn of the Father
We understand that all things bear record of Christ, and I think these have a pretty obvious application. Christ is the Firstborn of the Father's children. Like all other types of the firstborn, there is an attached blessing and responsibility to this office. The responsibility is fairly obvious; Jesus's mission was to come and offer salvation to all who would receive Him. He came to perform the Atonement, that men might have exaltation and eternal life.
This comes to my main point - the firstborn cannot share what he does not have, or give what hasn't first been given him. For Jesus to be the anointed one, to act as Saviour of mankind, he must have first been pre-saved, specially "redeemed" of his parents. I submit Jesus is a natural heir of salvation, or in other words, that him occupying the office of the firstborn, he is exclusively given the unconditional privelege of eternal life on account of birth. If it weren't so, he could never be called the messenger of the covenant, nor could he act as Saviour. One cannot lift another higher than to his own level. For Christ to save, he must have already been saved, even with the peculiar salvation of the firstborn, as typical in these and other scriptural examples.
Thoughts, ideas...?